Carved Into a Mountainside, This 1887 Carriage House Now Has a Second Life as a 'Palm Springs Meets the South of France' Pool House

At first glance, this 1887 Victorian carriage house in New Jersey looks every bit the historic outbuilding. But behind its timeworn façade lies an entirely different world: a sun-soaked pool house where brutalist concrete sits happily alongside disappearing walls of glass and reclaimed terracotta, and every room opens effortlessly onto the landscape. If there were ever a building that deserved a second act, it's this one.

Part of a wider renovation of a historic estate in Montclair, designer Michael Aiduss worked alongside Oasis Architecture to carefully weave a contemporary addition into the existing structure, allowing old and new to exist in harmony. Hidden in the hillside is a now resort-style escape inspired by the easy glamour of 'Palm Springs meets the South of France,' – the sort of place, as Michael puts it, where you're 'ready to kick off your shoes and grab a gin and tonic.'

Long before it became a destination for languid afternoons by the pool, this building served a far more practical role within the estate. Nestled into the steeply terraced gardens below the main residence, the historic carriage house remained full of character, but it no longer suited the way its owners wanted to live. With an existing swimming pool sitting disconnected at the top of the garden and nowhere to relax before or after a swim, the brief wasn't simply to restore the carriage house, but to reimagine it entirely. 'The owners were very committed to design and wanted to keep the bones and history of the carriage house while creating a modern retreat tucked into the landscape,' he explains.

Rather than allowing the contemporary addition to overpower the Victorian building, every decision was made with restraint, from preserving the original scale and proportions to using a slim glass connection that bridges old and new. 'Part of the success of the joining of the building is that the carriage house is built into the side of the mountain and disguises the integration of postmodern design,' says Michael. 'One of the most important things with this project is the simplicity of the palette and materials, knowing that the upper addition to the carriage house would be sharply modern in comparison to the original.'

That thoughtful balance extends beyond the architecture to the atmosphere itself. Michael describes the aesthetic as 'Palm Springs meets South of France in the 1950s' – a vision that combines the optimism of California with the warmth and romance of European living. 'Naturally, the project is in the States; however, it was hard to resist capturing the "joi de vivre" of summertime living,' he adds. It's evident everywhere, from reclaimed French terracotta and rough plaster to expanses of glass that dissolve into the surroundings. Yet for all its contemporary interventions, the project never feels as though it has been imposed on the original building.

You first arrive in the original garden room, where on a clear day, you can look out towards the New York skyline. 'I selected a reclaimed terracotta stone from France, laid with a more modern format, and the walls are rendered in a rough plaster which carries through both the historical and modern spaces connecting them in a seamless way,' Michael explains. 'It was necessary to use materials that could withstand time.' From there, the architecture begins to unfold. A slim expanse of glass subtly separates the original structure from its modern counterpart, creating a deliberate pause, while at the heart of the transitional space is the sculptural cast concrete and bronze staircase, designed to appear as if it is floating.

The lower level feels intimate, but as you ascend, daylight begins to flood in, materials become lighter, and the architecture unfolds towards the pool terrace, where floor-to-ceiling accordion doors dissolve the boundaries between inside and out. Michael describes the experience as stepping into 'a different time period, ready to kick off your shoes and grab a gin and tonic.' For all its architectural ambition, this is ultimately a space designed to be lived in with the doors wide open.

'The kitchen area is surrounded by floor-to-ceiling doors and windows that glide open to fully reveal the covered dining and sitting area of the pool terrace, making them feel as if they are one space,' says Michael. Beyond the kitchen, an outdoor cooking area doubles the entertaining opportunities, while a ten-foot dining table sits beneath a curved canopy overlooking the pool. Across the water, a pergola and fireplace create a quieter corner for long evenings, while the surrounding terraces, reimagined by landscape designer Susan Cohan, soften the architecture with a distinctly Californian spirit. It's this constant dialogue between architecture and landscape that gives the pool house its unmistakable sense of escape.

The open-plan kitchen is perhaps the clearest expression of the home's easy-going approach to summer living. Restrained rather than showy, its palette of warm oak cabinetry, softly veined stone and sculptural lighting feels quietly luxurious, allowing the landscape beyond to do much of the talking. At its centre, a monolithic stone island anchors the room, while open shelving and tactile natural materials keep the space feeling relaxed rather than overly polished. 'Altogether, these warm earth tones and materials captivate the senses and create a sense of calm,' Michael adds.

'The focus was to create a casual, easy-going atmosphere that encourages outdoor living and entertaining,' says Michael, and nowhere is that more apparent than in the living room. Deep, inviting sofas are arranged around an oversized coffee table and even larger screen 'for afternoon viewings', while carefully chosen vintage furnishings add character without competing with the clever architectural details, like the custom glass corners embedded with linen and the white oak ribbing that stretches behind the screen and over the ceiling. 'Although the second level is nestled into the mountainside, a ridgeline skylight was added to bring in as much light as possible in the center of the building,' he adds.

While the lower level is designed to spill outdoors, the loft embraces a cozier atmosphere. Tucked beneath the pitched roof and framed by the building's original arched windows, the former games room now offers a distinctly different mood to the open-plan spaces below. 'The walls are coated in a deep shade of terracotta plaster reminiscent of the antique floors on the ground floor, giving the impression of a warm sunny afternoon at any time of day,' Michael explains of the space, which is now used as a cossetting den for lounging, reading, and napping.

Running through the modern upper level, a glazed, greenhouse-inspired skylight washes the pool house in daylight. More than simply connecting the rooms, the light-filled, elongated gallery becomes a destination in itself, creating a gentle rhythm between the historic carriage house and the contemporary addition. That same design language continues into the bathroom, where the pitched skylight transforms what could have been a compact space into one that feels unexpectedly expansive. 'A full bath has been lined with soft ivory matte tile in combination with modular panels of concrete and travertine,' explains Michael. 'The materiality of the bathroom has been reinforced by utilizing natural materials that are synonymous with the rest of the design of the house.'

Rather than reading as a bold architectural statement, the entry demonstrates an exercise in balance, pairing the rawness of cast concrete with the warmth of terracotta tiles underfoot and softly plastered walls beyond. 'It was important to use materials that would translate in a synonymous way,' Michael explains. 'I was excited to combine brutalist concrete together with reclaimed 18th-century terracotta. The staircase floats in a brutalist way but also feels light and airy,' he adds.

Every detail was designed with entertainment in mind. From the entry, the greenhouse also provides ample space for wintering seasonal plants as well as dining. 'The clients can experience intimate dinners as well as various seating areas to facilitate multi-season use of this special space,' Michael adds. 'Anything from a long, narrow candle-lit dinner table, to ping-pong.' Meanwhile, the outdoor space was, of course, designed around the pool, but also boasts a large outdoor kitchen, a sitting area that 'affords a perfect city view that glistens a fiery orange color during afternoon sunsets', and a curved canopy held up by a Y-shaped brutalist column. 'Opposite the dining area, across the pool, is a pergola for shading the afternoon sun or intimate evenings by the fire,' he adds.

In many ways, this project is about far more than a beautifully designed pool house. It's a lesson in how thoughtful architecture can breathe new life into historic buildings without asking them to sacrifice their story. By balancing the carriage house's Victorian bones with a contemporary intervention, Michael has created a retreat that is both deeply rooted in its setting and wonderfully transportive.

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